Patent Document 1 discloses a control system for an internal combustion engine that estimates the temperature of a wall surface of a cylinder from an integrated value of intake air amount after starting the engine, shifts an ignition timing to an advanced side of the minimum advance for the best torque (MBT) in a case in which an estimated value of the temperature of the wall surface is lower than a threshold, and shifts the ignition timing to a retarded side of MBT in a case in which the estimated value of the temperature of the wall surface is equal to or greater than the threshold.